HCG Pregnancy Rapid Test

Intended Use

The reagent is used to detect the HCG in urine qualitatively according to the colloidal gold immunochromatographic test principle. It is used as an aid in the early detection of pregnancy. The reagent is suitable for professional use and self-testing.

HCG is a glycoprotein hormone secreted by placental syncytiotrophoblast cells, including two subunits A and ß. Its role is to stimulate the corpus luteum to continue to produce progesterone and make the endometrium suitable for embryo implantation. In normal pregnancy, HCG can be detected in both urine and serum as early as 7 to 10 days after conception, which can be tested in the urine of pregnant women after conception. HCG levels continue to rise very rapidly until delivery, peaking in about 8–10 weeks into pregnancy, and fall to normal level 2 weeks after the delivery. Its rapid increase in concentration during early gestational growth makes it an excellent marker for the early detection of pregnancy.

Test Principle

According to the colloidal gold immunochromatographic test principle, the nitrocellulose membrane is coated with HCG monoclonal antibody 2 and goat anti-mouse IgG antibody, the colloidal gold conjugate pad is labeled with HCG monoclonal antibody 1. When HCG is contained in the sample, it binds with the colloidal gold labeled monoclonal antibody to form a complex, moves forward under the chromatography, then combines with the coated antibody in the test region to form a colored line (Test line, T), which indicates a positive result. When the sample does not contain HCG, the complex cannot be formed, and no colored line appears in the test region, which indicates a negative result.

No matter whether the samples contain HCG or not, a colored line will always appear in the control line (C) region if the test has been performed properly.

Main Components

• Strip: Test strip (with desiccant packed in foil pouch), sample container and instruction for use.
• Cassette: Test cassette (with desiccant packed in foil pouch), sample container, disposable plastic straws, and instruction for use.
• Midstream: Test midstream (with desiccant packed in foil pouch), and instruction for use.

Specifications

Test Strip Kits

Components	1 Test	2 Tests	5 Tests	10 Tests	30 Tests	50 Tests	100 Tests
Test strip	1		5	10	30	50	100
Sample container		2		10	30	50	100
Instruction for use		1	1	1	1	1	1

Test Cassette Kits

Components	1 Test	2 Tests	5 Tests	10 Tests	25 Tests	40 Tests	50 Tests
Test cassette	1	2	5	10	25	40	50
Sample container	1			10	25	40	50
Disposable straws	1	2	5	10	25	40	50
Instruction for use	1	1	1	1	1	1	1

Midstream Kits

Components	1 Test	20 Tests	25 Tests
Test midstream	1	20	25
Instruction for use	1	1	1

Material Needed but Not Provided

• Timer

Storage and Expiry

Store in a dry environment at 4–30°C, avoid heat and sunshine, valid for 36 months.
DO NOT FREEZE.
Some protective measures should be taken in hot summer and cold winter to avoid high temperature or freeze-thaw.

Sample Requirements

• Urine samples should be collected in a clean, dry container. Urine can be detected within a day, but the highest concentration of HCG is usually in the morning urine.
• If the sample is not tested immediately, it can be stored at 2–8°C for up to 48 hours. For prolonged storage, samples may be frozen and stored below –20°C for 2 years.
• Frozen samples should be fully thawed and equilibrated to room temperature and shaken well before testing.
• When the urine sample appears turbid or precipitated, do not shake it and take the supernatant for testing.

Test Procedure

Instruction for use must be read entirely before taking the test.
Allow the reagent to equilibrate to room temperature for 30 minutes (10–30°C) prior to testing.
Do not open the inner packaging until ready; it must be used in one hour if opened (Humidity ≤ 60%, Temp: 10–30°C).
Please use immediately when the humidity exceeds 60%.

Strip Method

• Remove the strip from the sealed pouch, and do not touch the NC membrane.
• Put the end of the strip with arrow into the urine; the interface of urine should not exceed the MAX line.
• When red liquid migration appears in the read area, take out the strip.
• Place the strip on a clean and level surface, then start the timer.

Cassette Method

• Remove the cassette from the sealed pouch and put it onto the desk with the sample well up.
• Add 3 full drops (approx. 80–100 µL) of urine by the disposable plastic straws vertically to the sample well (S) of the cassette.
• Avoid the formation of bubbles and then start the timer.

Midstream Method

• Remove the midstream from the sealed pouch and remove the cap.
• Pee directly on the sample area on the front end of the midstream.
• When red liquid migration appears in the read area, take out the midstream.
• Be careful not to exceed the arrow.
• Cover the cap and place the midstream on a clean and level surface, then start the timer.

Observe the test result immediately within 5 minutes. The test result is invalid over 5 minutes.

The operation flow chat is as follows:

Result Explanation

• Positive: Two distinct colored lines appear. One line should be in the control region (C) and another line should be in the test region (T).
• Negative: One colored line appears in the control line region (C). No line appears in the test line region (T).
• Invalid: The result is invalid if no colored line appears in the control line region (C), even if a line appears in the test line region (T).

Limitations

• The reagent cannot determine the exact content of HCG. A confirmed pregnancy diagnosis should be made only by a physician after all clinical and laboratory findings have been evaluated.
• If pregnancy is still suspected, a first morning urine sample should be collected 24 to 72 hours later and tested.
• The HCG content in patients with ectopic pregnancy is lower than that in normal pregnancy, and false negative results may occur.
• If the test results are inconsistent with the expected results, it is recommended to go to the hospital to use B-ultrasound for diagnosis.
• If the test result is weakly positive, it is recommended to test the blood sample with other Methodology.

Quality Control

There are the test line and the control line on the surface of the reagent. Neither the test line nor the control line is visible in the result window before applying a sample. The control line is used for procedural control and should always appear if the test procedure is performed properly and the test reagents of the control line are working.

The appearance of control line (C) is confirmed sufficient sample volume; adequate membrane wicking and correct procedural technique.

Performance Characteristics

• Limit of detection: 25 mIU/mL
• Clinical trial results:
  A clinical evaluation was conducted on 245 samples comparing the results obtained using the HCG Pregnancy Rapid Test and other commercially available HCG tests.

HCG Test	Comparator Method	Total
Positive	75	75
Negative	0	170
Total	75	170	245

• PPA: 100% (95% CI: 95.13%–100.00%)
• NPA: 100% (95% CI: 97.79%–100.00%)
• OPA: 100% (95% CI: 98.64%–100

Explanation of Terms

• PPA: Positive Percent Agreement = True Positives / (True Positives + False Negatives)
• NPA: Negative Percent Agreement = True Negatives / (True Negatives + False Positives)
• OPA: Overall Percent Agreement = (True Positives + True Negatives) / Total
• Cl: Confidence Interval

3. Analytical Specificity

3.1 Interfering Substances

It showed that the following substances have no effect on the test results:

Name	Concentration	Results
Hemoglobin	0.8 mg/mL
Glucose	0.8 mg/mL	Negative
Acetaminophen	0.5 mg/mL	Negative
Albumin		Negative
Amoxicillin	0.5 mg/mL	Negative
	80 mg/mL	Negative
Aspirin	0.8 mg/mL	Negative
Bilirubin	0.5 mg/mL	Negative
Clomiphene Citrate	0.3 kg/mL	Negative
Ascorbic acid	0.4 mg/mL	Negative
Vitamin B1	0.8 mg/mL	Negative

3.2 Cross-Reactivity

It showed that the following substances have no effect on the test results:

Name	Concentration	Results
hLH	500 mlU/mL (0 mlU/mL HCG)	Negative
hLH	500 mlU/mL (25 mlU/mL HCG)	Positive
hFSH	1000 mlU/mL (0 mlU/mL HCG)	Negative
hFSH	1000 mlU/mL (25 mlU/mL HCG)	Positive
hTSH	1000 uIU/mL (0 mlU/mL HCG)	Negative
hTSH	1000 pIU/mL (25 mlU/mL HCG)	Positive

Repeatability

The results and the coloration degree should be consistent when detecting the 25 mlU/mL of HCG standards by 10 kits of the same batch.

Hook Effect

When the concentration of HCG exceeds 100000 mlU/mL, the detection result may be negative due to the hook effect, and the sample should be diluted and tested again.

Precautions

• The reagent is disposable and for in vitro diagnostic use only.
• The reagent should remain in the sealed pouches until use. If sealing problem happens, do not test. Do not use devices beyond the expiration date.
• Place the reagent at room temperature (10–30°C) for 30 minutes before use.
• The desiccant within the package is not eatable.
• As long as there is a colored line in the test region within the specified observation time, no matter how strong or weak the line is, it should be judged as a positive result. The colored line is strong when the concentration of HCG is high, and the control line may be weak. It is a normal phenomenon.
• In the case of incomplete abortion, there is still placental tissue remaining in the uterus, a positive result will appear.
• Certain gynecological diseases such as ovarian cysts and endometrial hyperplasia, certain tumor diseases such as hydatidiform mole, choriocarcinoma, teratoma of testis, etc., and gestational trophoblastic diseases, may have false positive results.
• Certain endocrine and metabolic diseases such as pituitary gland disease, hyperthyroidism, and menopausal syndrome can cause false positive results.
• Injection or oral administration of human chorionic gonadotropin may affect the detection results.
• Wastes such as testing devices and samples after use should be considered potentially hazardous and should be properly disposed of in the same manner as an infectious agent and discarded according to local regulations.
• The reagent should strictly follow the operating method, sample addition time and sample amount in the manual. After sample addition, the test device should be placed flat on the table to prevent the sample chromatography speed from being too fast or too slow, which will affect the test results.
• Observe the results at the specified time, too long or too short reaction time may affect the test results.
• You should not take any decision of medical relevance without first consulting your doctor.